This invention relates to a method and apparatus for producing fused bands of hook or loop fastener material and, more particularly, for bonding or fusing tabs of hook or loop fastener material to opposing ends of an elongated band of material. Further, the present invention relates to a method and apparatus for attaching tabs of material to an elongated band of material wherein an ultrasonic welding apparatus is used to activate a heat sensitive adhesive between the cooperating pieces of material.
Several apparatus are known for automatically attaching hook or loop fastener material such as VELCRO to a substrate piece of material wherein an ultrasonic welding device is used to activate a heat activatable adhesive for adhering the two materials to each other. One such device is shown in U.S. Pat. No. 4,411,721 to Wishart which discloses an apparatus for ultrasonically welding a patch of hook or loop fastener to a substrate in the form of a notebook binder. Individual binders are provided in a stack and are conveyed to a work station by means of pushers which position the substrate in alignment with welding horns above and below the substrate. A continuous tape of hook and loop fastener material is severed into individual patches and the patches are conveyed to the work station by a transport vacuum pad which transfers each patch to the welding horn, and the horn is provided with a vacuum for holding and conveying the patch onto the substrate.
U.S. Pat. No. 4,752,351 to Lunt discloses another apparatus for automatically feeding a hook or loop fastener material to a work station and cutting the material to form a patch for attachment to a substrate in an ultrasonic welding operation. In this apparatus, a welding horn cooperates with a spring biased operating block wherein movement of the welding horn downwardly into engagement with the block results in movement of the block to sever a patch of the hook or loop material which is also moved into engagement with the substrate during the downward movement of the welding horn. Subsequently, as the welding horn is moved upwardly, an accompanying upward movement of the operating block results in a forward feed of the hook or loop material in preparation for the next welding operation. It should be noted that in this apparatus the particular location of the substrate relative to the welding horn and patch to be welded must be regulated by an operator since there is no mechanism for controlling the location of the substrate.
While the above described apparatus provides satisfactory means for performing standard repetitive welding operations to attach hook or loop fastener material to substrates, these apparatus do not provide a means for producing a cut substrate of a predetermined length for receiving the hook or loop material. Further, the prior art devices fail to disclose an apparatus wherein tabs of hook or loop material may be attached to opposing ends of a length of a substrate material.
Accordingly, there is a need for a method and apparatus for attaching hook or loop fastener material to an elongated substrate wherein the tabs of material are attached to opposing ends of the substrate. In addition, there is a need for an apparatus wherein the elongated band of material forming a substrate is produced by the apparatus from a continuous length of substrate material and wherein the length of the band may be easily altered without altering the physical relationship between the elements forming the apparatus.